Well packer and hold down means

ABSTRACT

A resettable well packer having a body with expansible sealing means thereon; gripping means expansible for holding the sealing means against downward movement, a mandrel movable in said body; a setting member on the mandrel engageable with the body to expand the sealing means against said gripping means; and holddown lock means on said mandrel and body coacting with said gripping means to lock said body and sealing means against longitudinal movement in the well bore, and releasable and resettable to permit the packer to be anchored, released, and reset in different locations during a single trip. Said holddown means comprises expander means on said body normally resiliently held in expanding position, a locking sleeve movable with the mandrel to be engageable with said expander means to prevent movement thereof from said normal expanding position, and removable from such position to permit contraction of said expander means, and gripping means including a plurality of gripping slips on the mandrel movable into engagement with said expander means for expansion of said slips to gripping position, said locking sleeve preventing contraction of said expander means during expansion of said slips. Biasing means on the mandrel is movable to engage said gripping means for urging said gripping slips toward said expander means during movement of setting member to expand the sealing means, whereby the gripping slips are resiliently biased toward gripping position during expansion of the sealing means, and are positioned to grip and lock the packer against upward movement when the sealing means has been fully expanded, without damaging wear of the teeth of the gripping slips during such movement. A bypass flow passage between the body and mandrel is closable by sealable valve means on the setting member and body when the packer is set. Latch means on the mandrel and body holds said holddown means and sealing means in locking sealing position, and releasable means between said mandrel and latch means permits said mandrel to be moved to release said holddown locking means, seal means and gripping means for removal of the packer from the well bore if the latch means cannot be released.

United States Patent [72] Inventor Carter R. Young Dallas, Tex.

[211 App]. No. 816,939

[22] Filed Apr. 17, 1969 [45] Patented Mar. 16, 1971 [73] Assignee OtisEngineering Corporation Dallas, Tex.

[54] WELL PACKER AND HOLD DOWN MEANS 19Claims, 8 Drawing Figs.

Primary Examiner-Ian A. Calvert Attorney-E. Hastings Ackley ABSTRACT: Aresettable well packer having a body with expansible sealing meansthereon; gripping means expansible for holding the sealing means againstdownward movement, a mandrel movable in said body; a setting member onthe mandrel engageable with the body to expand the sealing means againstsaid gripping means; and holddown lock means on said mandrel and bodycoacting with said gripping means to lock said body and sealing meansagainst longitudinal movement in the well bore, and releasable andresettable to permit the packer to be anchored, released, and reset indifferent locations during a single trip. Said holddown means comprisesexpander means on said body normally resiliently held in expandingposition, a locking sleeve movable with the mandrel to be engageablewith said expander means to prevent movement thereof from said normalexpanding position, and removable from such position to permitcontraction of said expander means, and gripping means including aplurality of gripping slips on the mandrel movable into engagement withsaid expander means for expansion of said slips to gripping position,said locking sleeve preventing contraction of said expander means duringexpansion of said slips. Biasing means on the mandrel is movable toengage said gripping means for urging said gripping slips toward saidexpander means during movement of setting member to expand the sealingmeans, whereby the gripping slips are resiliently biased toward grippingposition during expansion of the sealing means, and are positioned-togrip and lock the packer against upward movement when the sealing meanshas been fully expanded, without damaging wear of the teeth of thegripping slips during such movement. A bypass flow passage between thebody and mandrel is closable by scalable valve means on the settingmember and body when the packer is set. Latch means on the mandrel andbody holds said holddown means and sealing means in locking sealingposition, and releasable means between said mandrel and latch meanspermits said mandrel to be moved to release said holddown locking means,seal means and gripping means for removal of the packer from the wellbore if the latch means cannot be released.

Patented March 16, 1971 I 3,570,596

4 Sheets-Sheet 1 r53 F|G 2 INVENTOR i 26 CARTER moums n29 as--5 1 I32 mZI I 7 use BY ATTORNEY Patented March 1, 1'71 4 Sheets-Sheet 2 INVENTORCARTER RYCUNG FIG-5 ATTORNEY Patented March m, 19% 3,570,596

4 Sheets-11991. 4

INVENTOR CARTER R. YOUNG ATTORNEY WELL PACKER HOLD WN WARE Thisinvention relates to well tools, and more particularly to locking andholddown means therefor.

One object of the invention is to provide a well packer for sealing theannulus between a string of well tubing and the wall of the well bore,and having means for anchoring it against movement in eitherlongitudinal direction.

Another object of the invention is to provide a well packer of thecharacter described which can be set, released and reset repeatedly andat various locations during a single trip of the packer into the wellbore, without removal of the packer from the well bore.

A further object is to provide a packer of the character set forthhaving gripping means for holding the same against downward movement andhold down lock means coacting therewith to lock said packer in sealingposition against movement in either longitudinal direction in the wellbore, said holddown lock means being releasable and resettable to permitthe packer to be anchored, released, and reset as described.

Yet another object is to provide a packer of the character describedhaving means providing a fluid bypass passageway therethrough tofacilitate lowering of the packer through the well bore and means forclosing said bypass passageway when said packer is set, said passagewaybeing reopenable during releasing of the packer to equalize anydifference in fluid pressures existing thereacross and to facilitateremoval of the packer from the well.

Another object is to provide a well packer of the character describedwherein the holddown lock means comprises collapsible frustoconicalexpander means normally resiliently held in expanding position and asupport or locking sleeve movable within said expander means to preventcollapsing movement thereof and movable from within said expander meansto permit same to be retracted from expanding position, and a pluralityof gripping slips engageable with said expander means for movementthereby to gripping hold down position.

A further object is to provide a well packer of the character describedhaving latch means on the mandrel and body engageable to latch saidpacker in set position with said bypass passageway closed, said latchmeans being releasable to permit movement of the mandrel to release thepacker.

A particular object of the invention is to provide a well packer of thecharacter described wherein the expander for the holddown lock meanscomprises a cylinder having a plurality of upstanding resilient fingershaving external bosses on their upper ends providing a frustoconical camexpander surface normally resiliently held in expanding position formoving said holddown slips outwardly into gripping position uponrelative movement of said upper slips-toward said expander means, andsupporting or lock sleeve means movable to a position to engage saidfingers to prevent inward movement of the bosses at the upper endthereof, said lock sleeve means being movable during releasing of saidpacker to a position out of position to engage said expander fingers topermit said fingers to yield inwardly, and engageable with said slips tomove said slips out of engagement with said expander surface to releasedposition.

Another important object is to provide a holddown lock mechanism for awell packer having a body with expansible sealing means thereon and amandrel having a setting member thereon movable with said mandrel toexpand said seal means, said holddown lock mechanism having grippingslips actuated by setting movement of the mandrel expanding the sealingmeans, and resiliently biased toward gripping position during suchsetting movement; and means for latching the mandrel and body ingripping sealing position until the latch is disengaged and the mandreland setting member are moved away from the body.

Additional objects and advantages of the invention will be readilyapparent from the reading of the following description of a deviceconstructed in accordance with the invention, and reference to theaccompanying drawings thereof, wherein:

FIGS. 1, 2 and 3 taken together are views, partly in elevation andpartly in section, of the upper, middle and lower portions of a welltool constructed in accordance with the well tool of the invention,showing the same in running condition; I

FIG. 4, FIG. 5, and P16. 6 are views similar to FIGS. 11, 2 and 3;showing the well tool set in anchored sealing position;

FIG. 7 is a fragmentary view, partly in elevation and partly in section,of the holddown and latching means of the well tool, showing the samebeing released; and,

FIG. 8 is a horizontal cross section view taken on the line 8-8 of HO.6.

In the drawings, the numeral 10 designates, generally, a well packerembodying the invention having an elongate tubular mandrel ll with acoupling 12 at its upper end and a connector sub 13 at itslower end, bymeans of which the mandrel may be connected to a well flow conductor ortubing string T for use within a casing C in a well bore.

Slidable longitudinally on the mandrel is an elongate tubula packing orsealing element supporting sleeve 15, the lower portion 16 of whichclosely slidably surrounds the mandrel and the upper portion l7 of whichis enlarged in diameter to provide an annular flow space 13 between saidupper portion of said sleeve and said mandrel. A plurality of lateralports 19 formed in the sleeve l5at the lower end of the enlarged portion17 provide entry for fluids into said annular bypass flow passagebetween said sleeve and the mandrel, and the upper end of said sleeve isopen to permit fluids to flow outwardly thereabove. Externally threadedon the upper end of the enlarged portion of the sleeve is a packingsupporting bushing 20 and a tubular expander and latching setting member21 is threaded onto the upper end of the bushing and extends upwardlytherefrom in circumferentially spaced relationship to the mandrel. Asetting ring 25 is confined in an internal annular recess formed in thesetting member between a downwardly facing shoulder 26 in the bore ofthe setting member and the upper end 27 of the packer supportingbushing. An internal annular seal assembly 39 is disposed in an intemalannular recess between the setting ring and an upwardly facing shoulder31 formed in the bore of the bushing above the upper end of the packingsupporting sleeve 15 for a purpose to be hereinafter explained.

Mounted on the exterior of the enlarged upper portion of the sleeve area plurality'of resilient elastomeric sealing elements or packing rings33 which are confined between the lower end of the packing supportingbushing 20 and the upper end of an annular expander wedge member 35which is slidable on the upper portion of the sleeve between theelastomeric rings and an external annular stop flange 37 formed at thelower end of the enlarged portion of the sleeve. The upper surface ofthe stop flange engages an internal annular shoulder 38 formed by aninternal annular flange 39 formed in the upper end of the bore of theexpander wedge member to retain the wedge member on the sleeve. Lateralflow openings 40 are provided in the wedge member communicating with theports 1? in the sleeve to permit ready access of fluid to the bypassflow passage between the sleeve and the mandrel.

Below the expander wedge member 35 is a slip carrier sleeve which isslidable on the reduced lower portion 16 of the packing supportingsleeve 15, and a plurality of serrated gripping slips 46 are slidablyconnected to said carrier by T- shaped handles 47 disposed in aninternal annular recess 48 and circumferentially spaced radiallyextending grooves 480 formed in said carrier. The T-shaped handles ofthe slips have their heads 49 engaged under the internal annularshoulder 50 formed by the recess 48 in the bore 51 of the slip carrierto prevent upward displacement of the slips from the carrier, and agarter spring 5% disposed in grooves 55 formed in the lower portion ofthe faces of the slips biases the slips inwardly toward retractedposition, as shown in MG. 3. The slips have internal tapered surfaces 58which are adapted to engage the corresponding frustoconical expandersurface 60 formed externally on the lower portion of the expander wedgemember,

whereby the slips are moved outwardly into gripping engagement with thewall of the well casing C or the well bore.

Also mounted on the slip carrier. below the slips is a frictionmechanism 66 comprising a plurality of friction shoes 67 which areslidably mounted in radially opening longitudinally extending slots 68formed in the slip carrier and which have ears 70 which engage anannular retaining ring 7 l at the upper end of the recesses and anannular longitudinally extending upstanding flange 72 on the upper endof a J-latch pin carrier 74 threaded onto the lower end of the slipcarrier. Helical coiled springs 76 disposed in recesses 77 formed in theinner faces 78 of the shoes and engaging a leaf spacer or support member79 in the inner portion of the recess bias the shoes outwardly tofrictionally engage the wall of the well casing for holding the slipcarrier stationary during setting of the lower slips. The sub 33 at thelower end of the mandrel ii is provided with a J-slot till in which theinner cylindrical end 81 of the J-latch pin 82 engages to releasablyconnect the sub with the slip carrier. The lower end 84 of the reducedlower portion 16 of the packer support sleeve engages the upper end 85of the sub to support the expander wedge member 35 above the slips,while the engagement of the latch pin 82 in the l-slot 89 holds theslips downwardly below the expander wedge so that the slips are notexpanded during movement of the packer into the well bore. When the.l-latch pin is released from the .l-slot, the friction mechanism 66will hold the slip carrier stationary and the packer support sleeve lmay be moved downwardly to move frustoconical expander surface 60 of theexpander wedge 35 between the slips to expand the same to grippingengagement with the wall of the well casing in the usual manner.

A plurality of elongate longitudinally extending slots 83 are formed inthe lower reduced portion id of the packer support sleeve and acorresponding number of guide pins 39 are threaded through the slipcarrier 44 with their inner end portions 90 engaging the longitudinalslots. This engagement of the inner ends of the pins 39 in the slotsprevents rotational movement of the slip carrier with respect to thesupport sleeve, for a purpose which will be hereinafter explained.

The structure of the packer hereinbefore described comprisessubstantially the usual valve-in-head type packer structure.

An improved valve structure and hold down latch or locking means 100 isprovided above the expander and latching setting member 21 at the upperend of the packer support sleeve. The upper end of the setting member isprovided with an enlarged bore 102 which receives the lower cylindricalportion 103 of a collapsible expander member M35. The expander member isformed with a plurality of longitudinally extending slots 106 whichprovide resilient upstanding fingers H07 having enlarged external bosses108 at their upper ends providing downwardly facing shoulders whichengage the upper end I ll) of the setting member. Suitable retainer pinsor set screws 114 are threaded or otherwise secured in radiallyextending openings in the setting member and engage in correspondingopenings formed in the expander sleeve, preferably in the longitudinalslots 106 formed between the fingers, so that the expander member isheld against upward displacement from the setting member. The outersurfaces or faces of the bosses are inclined inwardly or taper upwardlyabove the shoulders 109 to provide an expander surface 116, theplurality of such bosses providing asubstantially frustoconical expandermeans on the expander sleeve. The inner surfaces of the fingers at thebosses are formed with upwardly and outwardly inclined enlarged orrelieved bore portions 1118 which provide a shoulder 119 at the lowerend of such relieved portions, for a purpose to be hereinafterdescribed.

An upper slip assembly 125 includes a slip carrier or sleeve 126 havinga plurality of radially extending circumferentially spaced slots 127provided therein which are substantially T- shaped and which receive theT-shaped handles 129 projecting upwardly from upper gripping slips 130.The T-shaped radial slots in the carrier are formed by means of aninternal annular groove or recess 132 turned in the bore 133 of thesleeve and radially extending narrow slots 1127 cut through the lowerportion of the sleeve into the groove and into the bore of the sleevebelow the groove. The T-shaped handles of the slips fit in the slots andthe arms 135 of the T-shaped handles engage the lower upwardly facingsurface 136 of the internal annular groove to support and retain theslips on the carrier. The serrated external faces ldll of the slips havegrooves 141 in their upper portion in which a garter spring 142 isdisposed to bias the slips inwardly toward retracted position, as shownin H6. l. The inner surfaces 1414 of the lower portion of the slips areflared or inclined to correspond substantially to the frustoconicalwedgesurfaces 316 of the expander member, and when the slips are movedinto engagement with such frustoconical expander surfaces the slips aremoved outwardly into gripping engagement with the wall of the wellcasing or well bore to hold the packing supporting sleeve l againstupward movement therein.

An elongate expander and lock sleeve is slidable on the packer mandrel11 between an upwardly facing shoulder 152 at the upper end of anexternal annular flange 153 formed on the mandrel and the lower end ofaprojecting stop ring 155 which is titted into an external annular groove156 provided near the upper end in the mandrel above the upper end ofthe support and lock sleeve. An enlarged support and lock surface M8 isformed on the lower portion of the expander and lock sleeve and thissurface is tapered downwardly slightly to fit closely within theinternal enlarged or relieved portions 118 at the upper ends of theresilient fingers of the expander member m5, so that the support surfaceis disposed to engage such inner surfaces of the fingers behind thebosses to retain the bosses in their normal operative expanding positionshown in H6. 1. The engagement of he lower end of the lock sleeve R50with the upwardly facing shoulder l2 on the mandrel holds the sleeveupwardly out of engagement between the fingers of the expander memberwhile the packer is being run into the well bore. Also, the upwardlyfacing shoulder at the upper end of the enlarged lock surface of thelock sleeve engages under downwardly facing shoulders Ml fonned on theinner sides of the T-shaped handles of the upper gripping slips, wherebythe upper gripping slips are held upwardly out of engagement with theexpander surfaces 116 of the expander member as shown in FlG. 1, and theslip carrier and slips are thus supported by such upwardly facingshoulder. A projecting retainer ring 170 is secured within an externalannular groove l'i'l formed in the upper end portion of the expander andlock sleeve to limit upward movement of the slip carrier 1 .26 on saidsleeve and to retain the slip carrier in place thereon.

A biasing sleeve is slidably secured on the mandrel 11 above theretainer or stop ring 15$, and is slidable thereon below an upperprojecting split retainer or stop ring 376 secured in an externalannular groove 177 at the upper end of the mandrel, as clearly shown inFIG. 1. The biasing sleeve is formed with an internal annular upwardlyfacing shoulder 179 in its lower portion which supports a lower biasingand guide ring 13 1 held in place in the enlarged bore of the biasingsleeve by a retaining screw 181 disposed in an opening in the sleeve andthreaded into a threaded opening in said ring. The

lower biasing and guide ring engages the upper edge of the retainer orstop ring 155 on the mandrel to limit downward movement of the biasingsleeve, and the retaining screw 181 threaded into the biasing ring holdsthe biasing sleeve against downward movement beyond that point. Ahelical coiled spring 184 is supported at one end on the'upper face ofthe biasing ring and has its other end resiliently engaging the lowerend of an upper biasing and guide ring 186 which is slidable in theupper portion of the enlarged bore l88 of the biasing sleeve and whichengages the lower end of the projecting upper retaining or stop ring 176on the mandrel. it will, therefore, be seen that the spring we actingagainst the lower biasing ring biases the biasing sleeve i175 downwardlyat all times, and that the sleeve may be moved upwardly by com pressingthe spring between the lower biasing ring and the upper biasing andguide ring. The lower end of the biasing sleeve telescopes over theupper end of the expander and lock sleeve 150 and engages the upper endof the slip carrier 126, when the mandrel is moved downwardly withrespect to the slip carrier and the expander and lock sleeve as shown inFIG. 4. Such engagement of the biasing sleeve with the slip carrierbiases the slip carrier and the slips supported thereby toward theexpander surfaces 116 at the upper end of the expander sleeve 105, sothat the slips are biased toward said expander surface by said springbut may move upwardly away from expanded position as the mandrel movesdownwardly, for a purpose to be hereinafter more fully explained.

A packing expander and latch sleeve 2% is secured on the mandreladjacent and below the external annular flange 153 in the median portionof the mandrel and is held in such position by a shear pin or screw 202threaded through the latch sleeve into a threaded recess 294 formed inthe exterior of the mandrel so that the packing expander and latchsleeve 200 is held against movement on the mandrel so long as said shearpin or screw 292 is intact. The packing expander and latch sleeve isprovided with a plurality of J-slots 208 in the enlarged upper portion299 thereof and has a downwardly facing beveled shoulder 210 in itsmedian portion which is adapted to engage the upper beveled face 212 ofthe expander ring in the bore of the expander and latching settingmember when the mandrel is moved downwardly, whereby the mandrel, actingthrough the packing and expander and latch sleeve will force saidpacking supporting sleeve downwardly with respect to the lower expandermember 35 and compress the packing rings 33 between said lower expandermember and the downwardly facing shoulder 220 at the lower end of theexpanderbushing at the upper end of said supporting sleeve. The lowerexpander wedge member 35 is slidable upwardly on the upper enlargedportion 17 of the support sleeve above the exter nal annular flange 37when the lower slips 46 are expanded into gripping engagement with thewell casing, so that downward movement of the packing supporting sleeveby the mandrel will compress the packing rings 33 and expand the samebetween the expander wedge 35 and the downwardly facing shoulder 220 onthe packing expander bushing to expand the packing rings into sealingengagement with the wall of the well easing. J-pins or lugs 224 arethreaded through suitable threaded openings in the expander and latchingsetting member and have cylindrical inner ends 225 which project intothe bore of the setting member and-are disposed to engage in the J-slots208 formed in the expander and latch sleeve. When the J-pins or lugs areengaged in the J-slots, the mandrel is locked to the expander and latchsleeve and the reduced lower portion 226 of the expander and latchsleeve engages-the seal assembly 30 to close the upper end of the bypasspassage 18 through the packing supporting sleeve and prevent fluid flowtherethrough.

An O-ring seal member 230 is disposed in an external annular groove inexternal flange 153 on the mandrel for sealing between the mandrel andthe upper portion of the expander and latch sleeve 2% so that fluidscannot flow exteriorly of the mandrel between the external packing ringson the supporting sleeve 15 in either direction.

By varying the thickness of the spacer leaves 79 in the slots 68 in theslots 68 in the slip carrier 44 in which the friction shoes 67 aremounted, it is possible to adjust the load or force of the springs 76acting on the friction shoes 67. Heavier casing having a smaller boremay not require a spacer leaf, while lighter casing with a largerdiameter bore may require the use of a spacer leaf to maintain properloading on the springs and the friction shoes for correct operation ofthe packer.

In use, the well tool or packer 10 is connected by means of the coupling12 at its upper end to the lower end of the tubing string T; and, ifdesired, additional lengths of tubing may be connected by the usualcouplings to the lower end of the sub 13 at the lower end of the mandrell l and extend downwardly to a desired depth therebelow. The parts ofthe packer are disposed in the positions shown in FIGS. 1, 2 and 3, andthe packer is lowered into the well casing with the parts in suchposition.

The friction element shoes 67 will engage the bore wall of the casing Cand drag thereagainst as the packer is lowered through the casing.However, the .l-slot connection of the pin .well. The upper slips 130 ofthe hold down gripping means are held in the retracted position byvirtue of the engagement of the lower end of the expander and locksleeve 1150 with the shoulder 152 of the flange 153 on the midportion ofthe mandrel.

When the desired depth in the well at which the packer is to be set hasbeen reached the tubing string is turned, normally in a counterclockwisedirection, with respect to the friction mechanism 66 to disengage thelug 81 from the J-slot 80, the friction mechanism holding the slipcarrier 44 against rotation while the mandrel 11 and the supportingsleeve 15 are rotated with respect thereto, the guide pins 89 engaged inthe slots 88 in the lower portion of the supporting sleeve turning saidsupporting sleeve with respect to the slip carrier 44 and lower slips46.

When the J-lug and J-slot have been disengaged, in the usual manner, thetubing string T is lowered to lower the mandrel and the supportingsleeve 15 therewith until the lower expander member 35 engages theslips, and the tapered surface 60 of the expander member engages theinclined surfaces 58 within the slips to wedge the same outwardly intogripping engagement with the wall of the well casing in the usualmanner. A sufficient downward force applied to the mandrel will thencause the lower expander member, which is held against further downwardmovement by the slips 46, to move upwardly on the upper portion 17 of.the packing supporting sleeve 15 to compress the packing rings 33thereon. Downward movement of the mandrel with respect to the supportingsleeve moves the packing expander and latch sleeve 2% downwardly withthe mandrel until the downwardly facing shoulder 210 on the latch sleeveengages the upwardly facing beveled shoulder 212 at the upper end of theexpander ring 25 in the bore 'of the expander and setting member 21 atthe upper end of the packing supporting sleeve. Further downward forceapplied by the mandrel to the upper end of the supporting sleeve willfully compress the sealing rings 33 on the exterior of the supportingsleeve between the downwardly facing shoulder 220 on the expanderbushing 20 and the upwardly facing upper end of the lower expandermember 35, and at the same time will force the expander member stillmore tightly between the slips to provide a tighter gripping engagementof the slips with the wall of the well casing, while at the same timethe packing rings are fully expanded or deformed into tight sealingengagement with the wall of the well casing.

As the mandrel moves downwardly in effecting setting movement of thesealing rings 33 and the lower slips 46, the gripping slips of the holddown gripping means 125 above the supporting sleeve l5are permitted tomove downwardly with respect to the expander means 105 at the upper endof the supporting sleeve. The gripping slips of the hold down means willengage the wedge surfaces 116 on the upper ends of the spring fingers107 of the collapsible expander slee ye 105 and be biased outwardlythereby; At the same time, enlarged support and lock surface 158 at thelower end of the support and lock sleeve enters between the enlargedrelieved portions 118 within the upper ends of the fingers and isdisposed to hold the fingers against inward movement. The lock surface158 will move downwardly until the shoulder at the lower end thereofengages the upwardly facing shoulder 119 at the lower end of therelieved inner portions of the fingers behind the bosses 108. Theenlarged support and lock surface 158 on the expander and lock sleeve15% therefore prevents inward collapsing deformation of the resilientfingers M97 of the upper expander member 105 and holds the same inposition for the frustoconical wedge surface 116 providedlby the bossesat the upper ends of the fingers in position to force the gripping slips130 of the hold down means 125 outwardly toward gripping position. itwill be noted that the expander lock sleeve 150 is movablelongitudinally on the mandrel 11 between the upwardly facing shoulder152 on the external flange 153 on the mandrel and the downwardly facingshoulder at the lower end of the lower stop ring 155 on the mandrel.When the downwardly facing shoulder on the lower stop ring engages theupper end of the expander and lock sleeve, the sleeve is positivelyforced downwardly between the upper ends of the fingers of the upperexpander member, while the biasing sleeve 175 yieldably engages theupper end of the slip carrier 126 supporting the gripping slips 130 ofthe hold down means 125, so that the slips are not positively forcedoutwardly on the frustoconical outer or expander surfaces 116 at theupper ends of the fingers 107 by such downward movement of the mandrel.When the expander and latch sleeve 200 and the expander and lock sleeve150 have been moved downwardly to their lowermost positions, thedownward force applied by tubing to the upper end of the packingsupporting sleeve 15 expands or deforms the sealing rings 33 on thesupporting sleeve, while at the same time the biasing sleeve 175yieldably urges but does not force the gripping slips 130 of the holddown means 125 toward gripping position on the wedge surfaces 116 of theexpander member 105 of said hold down means.

When downward pressure of the tubing string is reduced so that themandrel 11 may move upwardly slightly, the wedge surfaces 116 of thebosses 108 on the expander member 105 of the hold down means 125 forcethe gripping slips 131) of said hold down means into tight grippingengagement with the wall of the well casing C to prevent upward movementof the upper end of the latching setting member 21 and the supportingsleeve 15, and so lock the supporting sleeve against upward movement inthe well casing. Simultaneously, the Jslots 208 formed in the enlargedupper portion of the expander and latch sleeve 200 will engage theprojecting cylindrical inner portions of the J-lugs carried by thesetting member 21 and will turn the tubing slightly until the J-lugs areengaged with said .l-slots to prevent upward movement of said latchsleeve 200 and the mandrel 11 connected therewith by means of the shearpin 202. The mandrel is therefore locked in its lower position and thepacker is locked in set sealing position.

The yieldable resilient biasing of the gripping slips 130 of the holddown means 125 by the biasing sleeve 175 and the spring actingthereagainst permits such slips to move downwardly with respect to thewell casing following the expander 105 until the packing rings have beenthoroughly set and until the downward force on the supporting sleeve isreleased. Thus, the teeth of the gripping slips will not be damagedduring such downward movement, and at the same time the slips arepositively moved by said resilient means into position to positivelygrip the wall of the casing when the downward force on the mandrel isreduced or released.

To release the packer for resetting at another location in the casing orfor removal from the well bore, the tubing is rotated to rotate the J-slots of the expander and latch sleeve 200 from locking engagement withthe J-lugs 224 of the setting member 21, and the mandrel is movedupwardly. The shoulder 152 on the upper end of the flange 153 in themedian portion of the mandrel engages the lower end of the expander andlock sleeve 150 and moved the same upwardly to move the enlarged locksurface 158 thereof from within the downwardly or relieved tapered innerfaces 118 at the upper end of the tingers 107 of the expander member 105of the hold down means. The taper of the inner surfaces of the fingersand the enlarged lock surface of the lock sleeve 150 permits easyremoval of such enlarged surface from within the fingers. Continuedupward movement of the mandrel and the lock sleeve will cause theshoulder 160 at the upper end of the enlarged portion 158 of the locksleeve to engage the downwardly facing shoulders 161 on the inner facesof the slip handles and lift the slips upwardly off the wedge surfaces116 on the outer faces of the bosses 108 at the upper ends of thefingers 107 of the expander member 1.05 of the hold down means. Upwardmovement of the slips is also facilitated by virtue of the fact that theupper ends of the fingers of the expander member may flex inwardlytoward a contracted or collapsed position to permit the gripping slipsto release easily from gripping engagement with the wall of the casing,since the enlarged lock surface 158 no longer is in position to restrainor prevent such inward flexing movement of the upper ends of thefingers.

Continued upward movement of the mandrel will then move the sub 13 atthe lower end of the mandrel into engagement with the lower end 84 ofthe packing supporting sleeve 15 and lift the supporting sleeve untilthe upwardly facing shoulder on the flange 37 at the lower end of theenlarged upper portion 17 of the sleeve engages the downwardly facingshoulder 38 in the bore 39 of the lower expander member 35 and liftssuch expander member upwardly out of expanding engagement with the lowergripping slips 46 to release the gripping slips for inward movement toretracted position by the garter spring 55 surrounding the slips.Further upward movement moves the J-slots of the sub 13 into engagementwith the J-lugs 82 on the lower end of the carrier 74 and the J- lugsmay be moved to the lower portion of the J-slots and the tubing rotated,normally in a clockwise direction, to rotate the .l-lugs into latchingengagement with the J-slots to hold the slips in their lower position.Of course, such movement is not necessary unless the packer is to bemoved downwardly in the well casing to a lower position subsequent toreleasing the same from its previously locked sealing position. In anyevent, the packer parts are now again in the position shown in FIGS. 1,2 and 3, and the packer may be moved either upwardly or downwardly inthe well casing to a new location for resetting in the manner alreadydescribed, or may be removed from th well bore.

Should it ever develop that the latch sleeve 200 on the mandrel cannotbe released form the .l-pins 224 in the expander and latching settingmember 21, the shear pin 202 screw threaded through the latch sleeveinto the recess 204 in the mandrel may be sheared, as shown in FIG. 7,to permit the mandrel to move upwardly with respect to said settingmember and thus permit the upwardly facing shoulder 152 at the upper endof the flange 153 at the median portion of the mandrel to engage thelower end of the expander and lock sleeve to lift the same, and thencontinue with the release of the packer in the manner already describedto permit complete removal of the packer from the well bore.

From the foregoing, it will be seen that a well packer for sealing theannulus between a string of well tubing and the wall of the well borehas been provided, having means for locking it against movement ineither longitudinal direction, the packer being settable, releasable,and resettable to permit it to be anchored, released and reset in thewell casing during a single trip into the well without removing it fromthe well. it will also be seen that an improved hold down means has beenprovided which includes a collapsible frustoconical expander meansnormally resiliently held in expanding position, and a support or locksleeve movable with respect to the expander means to prevent collapsingor retracting movement thereof, said support or lock sleeve beingremovable from within the expander means to permit the same to beretracted when the well tool is to be removed from the well bore.Additionally, the packer has been provided with gripping slips in thehold down means which are resiliently biased toward gripping positionduring movement of the packer toward expanded position and which are notpositively forced toward said expanded position during such movement. Itwill also be seen that the hold down means is provided with means forpositively retracting the slips of the hold down means from engagementwith the expanding surfaces of the expander member of the hold downmeans and that such expander surfaces are contractable inwardly topermit said releasing movement without difficulty. Further, a valvemember has been provided for closing an annular bypass between theexternal seal rings and the mandrel which is openable and closable onmovement of the mandrel with respect to the support for the seal ring.Also, the setting means for setting the seal means is provided withlatch means for holding the same in locked sealing position in the wellcasing and yieldable upon application of a predetermined force theretoto permit the mandrel to be moved to release the hold down means and toretract the packer elements from gripping sealing position.

The foregoing description of the invention is explanatory only, andchanges in the details of the constructions illustrated may be made by,those skilled in the art, within the scope of the appended claims,without departing from the spirit of the invention.

lclaim:

1. A well tool including: an elongate tubular mandrel; a tubular bodyslidably mounted on said mandrel; sealing means surrounding said bodyand expansible to seal between said body and a well bore wall; firstgripping means on said mandrel and first expander means on said body onone side of said sealing means and engageable to .expand said firstgripping means to grip said well bore wall to prevent movement of saidbody in one longitudinal direction; holddown means comprising secondgripping means on said mandrel and second expander means on said body onthe side of said sealing means opposite to said first gripping means,said second expander means being collapsible inwardly and normally heldin expanding position to engage said second gripping means to expandsaid second gripping means to grip saidwell bore wall to preventmovement of said body in the opposite longitudinal direction; settingmeans on said mandrel movable longitudinally therewith to engage saidbody upon movement of said mandrel in one longitudinal directionrelative to said body for expanding said first gripping means togripping position and for expanding said sealing means to sealingposition; resilient means on said mandrel movable to bias said secondgripping means of said holddown means toward said second expander meansto move said holddown means togripping position, said resilient meansbeing actuatable to move said holddown means to gripping position bylongitudinal movement of said mandrel in said one longitudinaldirection; and latch means on said mandrel and said body coengageable topositively latch the mandrel in position holding said first grippingmeans, said sealing means and said holddown means in gripping sealingposition, said latch means being disengageable for movement of saidmandrel longitudinally with respect to said body in a direction oppositesaid one direction to release said first gripping means, said sealingmeans and said holddown means from said gripping sealing position.

2. The well tool of claim 1, wherein said longitudinal movement of saidmandrel in said opposite direction moves said sealing means, said firstgripping means, and said holddown means to unexpanded nongripping,nonsealing position, and wherein said mandrel is subsequently movable insaid one direction to again move said first gripping means, saidsealing.

means and said holddown means to expanded gripping sealing position.

3. The well tool of claim 1 including: means providing a fluid bypasspassageway between said sealing means and said tubular mandrel forequalizing pressures in the well bore above and below said sealingmeans; and valve closure means on said mandrel and said body engageablefor closing said bypass passageway against fluid flow therethrough.

4. The well tool of claim l wherein said expander means of said holddownmeans comprises: resiliently collapsible frustoconical expander wedgemeans mounted on said body; a support sleeve mounted on said mandrel ina first position spaced from said wedge means and movable to a secondposition to engage said wedge means to prevent collapsing movementthereof, said support sleeve being again movable to said first positionaway from said wedge means to permit the same to be collapsed; andsecond gripping means of said holddown means includes a carrier havingaplurality of gripping slips carried thereby and movable toward saidwedge means to engage said slips with said wedge means to move saidslips to id gripping position upon movement of said mandrel in said onedirection longitudinally relative to said body.

5. The well tool of claim ll wherein said second expander means-of saidholddown means is normally resiliently biased to expanding position andis resiliently contractable from such expanding position to release saidsecond gripping means o f said holddown means for movement from grippingposition.

6. A well packer including: an elongate tubular mandrel; tubular supportmeans slidably mounted on said mandrel; sealing means disposedexteriorly on said support means and expandable into sealing engagementwith the wall of the well bore; first expansible and retractable gippingmeans carried on said mandrel and first expander means carried by saidsupport means on onelongitudinal side of said sealing means andcoengageable to expand said first gripping means into engagement withthe well bore wall to prevent longitudinal movement of said supportmeans in one longitudinal direction;

holddown means carried on said mandrel and said support means on theopposite longitudinal side of said sealing means from said firstgripping means and first expander means and" expansible into engagementwith-the well bore wall to prevent movement of said support means in theopposite longitudinal direction, said holddown means comprising acarrier and a plurality of gripping members carried by one ofsaidtubular mandreland said support means and second'expand'er meanscarried by the other of said tubular mandrel and said support means andengageable with said gripping members to move the same to grippingposition; said expander means being normally resiliently held inexpanding position. for engagement with said gripping members andcontractable from such expanding position to permit release of saidgripping'members from gripping position; lock means on said mandrelmovable therewith from a position spaced from said second expander meansto a position to engage and support said second expander means in saidexpanding position; and resilient means on said mandrel movabletherewith from a position spaced from said holddown means to engage thecarrier to bias saidgripping members toward said second expander meanswhile. said lock means is engaged with said second expander means.

7. A well packer of the character set forth in claim 6 including: meansproviding a fluid bypasspassageway between said mandrel and said supportmeans; valve seat means on one and valve closure means on the other ofsaid mandrel and said support means engageable to close said bypasspassageway against fluid flow therethrough when said well packer is inset position in the well bore.

8%. A well packer of the character set forth in claim 7-, wherein. saidvalve closure means engages said valve seatmeans to close said bypasspassageway between said mandrel and said support means before saidsealing means is moved to sealing position.

9. A well packer of the character set forth in claim 6, wherein saidsecond expander means of said holddown means comprises a collet sleevehaving a plurality of resilient fingers with wedge expander means ontheir free ends normally resiliently held disposed in expanding positionby said fingers and contractable by flexing of said fingers to permitrelease of said gripping members from gripping position.

ill. A well packer of the character set forth in claim 6, wherein saidresilient means comprises: sleeve means disposed about said mandrel andspaced therefrom, and having means therein providing an internal annularupwardly facing shoulder intermediate the ends of the bore of saidsleeve means; means on said mandrel providing a downwardly facing stopand guide means disposed within the bore of said sleeve above saidupwardly facing shoulder; and spring means mounted between said mandreland said sleeve means with the ends thereof engaging said downwardlyfacing guide means onsaid mandrel and said upwardly facing shoulder insaid sleeve means, whereby said spring means biases the lower end ofsaid sleeve into engagement with said gripping means to urge saidgripping means to gripping. position when said mandrel is moved to movesaid packer to set position.

11. A well packer of the character set forth in claim lit) including:operator means on said mandrel movable therewith and engageable withsaid support means to move said support means through said sealing meanstoward said first gripping means after said first gripping means hasbeen expanded to gripping position to expand said sealing means intosealing engagement with the wall of the well bore, said resilient meanssimultaneously yieldably urging said gripping members of said holddownmeans to gripping position during said movement of said mandrel andsupport means.

12. A well packer of the character set forth in claim 11, wherein saidoperator means is slidably carried by said mandrel and engageable withsaid support means for moving said support means to expand said sealingmeans; and yieldable connecting means is provided between said operatormeans and said mandrel releasable to permit said mandrel to move withrespect to said operator means to release said packer from expandedlocked sealing position.

13. A well packer of the character set forth in claim 10, wherein thespring biased sleeve means of said resilient means is engageable withsaid gripping members of said holddown means to urge the grippingmembers thereof into expanding engagement with said second expandermeans and to maintain said gripping members in expanding engagement withsaid second expander means during longitudinal movement of said mandrelsetting said packer.

14. A well packer of the character set forth in claim 6, including: borewall engaging friction means connected with said first gripping means;and means releasably connecting said mandrel with said friction meansand said first gripping means and releasable to permit movement of saidmandrel relative thereto and with respect to said support means; meanson said mandrel engageable with said support means to move said supportmeans toward said friction means to expand said first gripping means togripping position; and means on said mandrel engageable with saidsupport means to move said support means through said sealing meanstoward said first gripping means to expand said sealing means to sealingposition after said first gripping means is moved to gripping position.

15. A well packer of the character set forth in claim 14 wherein: saidlock means on said mandrel is movable therewith out of supportingengagement with said second expander means of said holddown means tofree said second expander means for movement from expanding position topermit release of said gripping members of said holddown means fromgripping position.

l6. As a subcombination: a tubular mandrel; a tubular body surroundingsaid mandrel and slidable longitudinally with respect thereto; expandermeans on said body comprising a cylindrical sleeve formed with aplurality of normally expanded resilient fingers having external bosseson their free ends providing cam surfaces; locking sleeve means on saidmandrel movable therewith from a position out of engagement with saidexpanderfingers to a position to engage and support said expanderfingers against movement toward retracted position; gripping meanscomprising a carrier and a plurality of slips mounted on saidmandrel-and movable therewith to engage said expander cam surfaces toexpand said slips to gripping position; and biasing means on saidmandrel movable therewith from a position spaces longitudinally fromsaid gripping means to engage said carrier of said gripping for biasingsaid gripping means toward said expander cam surfaces to maintain saidslips engaged with said cam surfaces when said mandrel is moved relativeto said body means in a direction to move said locking sleeve means intoposition to engage and support said expander fingers against retractionand to move said gripping means toward said expander means.

17. In the subcombination of claim 16, coengageable latch means on saidlocking sleeve means and on said tubular body releasably engageable tosecure 'said'mandrel to said tubular body to hold said gripping means ingripping position and diseggageable to release said mandrel fromconnection to said b y for longitudinal movement with respect thereto torelease said gripping means from gripping position.

18. In the subcombination of claim 17, means providing a longitudinalflow passage between said tubular body and said mandrel; and valveclosure and seat means on said mandrel and said body engageable to closeoff flow through said flow passage when said mandrel islatched to saidbody.

19. The subcombination of claim 17, wherein said locking sleeve means isslidable longitudinally of said mandrel; and means is provided yieldablysecuring said locking sleeve means to said mandrel and yieldable uponapplication of a predetermined longitudinal force to said mandrel tofree said mandrel from securement to said locking sleeve means formovement of said mandrel with respect to said locking sleeve means topermit said mandrel to be moved to move said biasing to release saidgripping means without disengagement of said latch means.

1. A well tool including: an elongate tubular mandrel; a tubular bodyslidably mounted on said mandrel; sealing means surrounding said bodyand expansible to seal between said body and a well bore wall; firstgripping means on said mandrel and first expander means on said body onone side of said sealing means and engageable to expand said firstgripping means to grip said well bore wall to prevent movement of saidbody in one longitudinal direction; holddown means comprising secondgripping means on said mandrel and second expander means on said body onthe side of said sealing means opposite to said first gripping means,said second expander means being collapsible inwardly and normally heldin expanding position to engage said second gripping means to expandsaid second gripping means to grip said well bore wall to preventmovement of said body in the opposite longitudinal direction; settingmeans on said mandrel movable longitudinally therewith to engage saidbody upon movement of said mandrel in one longitudinal directionrelative to said body for expanding said first gripping means togripping position and for expanding said sealing means to sealingposition; resilient means on said mandrel movable to bias said secondgripping means of said holddown means toward said second expander meansto move said holddown means to gripping position, said resilient meansbeing actuatable to move said holddown means to gripping position bylongitudinal movement of said mandrel in said one longitudinaldirection; and latch means on said mandrel and said body coengageable topositively latch the mandrel in position holding said first grippingmeans, said sealing means and said holddown means in gripping sealingposition, said latch means being disengageable for movement of saidmandrel longitudinally with respect to said body in a direction oppositesaid one direction to release said first gripping means, said sealingmeans and said holddown means from said gripping sealing position. 2.The well tool of claim 1, wherein said longitudinal movement of saidmandrel in said opposite direction moves said sealing means, said firstgripping means, and said holddown means to unexpanded nongripping,nonsealing position, and wherein said mandrel is subsequently movable insaid one direction to again move said first gripping means, said sealingmeans and said holddown means to eXpanded gripping sealing position. 3.The well tool of claim 1 including: means providing a fluid bypasspassageway between said sealing means and said tubular mandrel forequalizing pressures in the well bore above and below said sealingmeans; and valve closure means on said mandrel and said body engageablefor closing said bypass passageway against fluid flow therethrough. 4.The well tool of claim 1 wherein said expander means of said holddownmeans comprises: resiliently collapsible frustoconical expander wedgemeans mounted on said body; a support sleeve mounted on said mandrel ina first position spaced from said wedge means and movable to a secondposition to engage said wedge means to prevent collapsing movementthereof, said support sleeve being again movable to said first positionaway from said wedge means to permit the same to be collapsed; andsecond gripping means of said holddown means includes a carrier having aplurality of gripping slips carried thereby and movable toward saidwedge means to engage said slips with said wedge means to move saidslips to gripping position upon movement of said mandrel in said onedirection longitudinally relative to said body.
 5. The well tool ofclaim 1 wherein said second expander means of said holddown means isnormally resiliently biased to expanding position and is resilientlycontractable from such expanding position to release said secondgripping means of said holddown means for movement from grippingposition.
 6. A well packer including: an elongate tubular mandrel;tubular support means slidably mounted on said mandrel; sealing meansdisposed exteriorly on said support means and expandable into sealingengagement with the wall of the well bore; first expansible andretractable gripping means carried on said mandrel and first expandermeans carried by said support means on one longitudinal side of saidsealing means and coengageable to expand said first gripping means intoengagement with the well bore wall to prevent longitudinal movement ofsaid support means in one longitudinal direction; holddown means carriedon said mandrel and said support means on the opposite longitudinal sideof said sealing means from said first gripping means and first expandermeans and expansible into engagement with the well bore wall to preventmovement of said support means in the opposite longitudinal direction,said holddown means comprising a carrier and a plurality of grippingmembers carried by one of said tubular mandrel and said support meansand second expander means carried by the other of said tubular mandreland said support means and engageable with said gripping members to movethe same to gripping position; said expander means being normallyresiliently held in expanding position for engagement with said grippingmembers and contractable from such expanding position to permit releaseof said gripping members from gripping position; lock means on saidmandrel movable therewith from a position spaced from said secondexpander means to a position to engage and support said second expandermeans in said expanding position; and resilient means on said mandrelmovable therewith from a position spaced from said holddown means toengage the carrier to bias said gripping members toward said secondexpander means while said lock means is engaged with said secondexpander means.
 7. A well packer of the character set forth in claim 6including: means providing a fluid bypass passageway between saidmandrel and said support means; valve seat means on one and valveclosure means on the other of said mandrel and said support meansengageable to close said bypass passageway against fluid flowtherethrough when said well packer is in set position in the well bore.8. A well packer of the character set forth in claim 7, wherein saidvalve closure means engages said valve seat means to close said bypasspassageway between said mandrel and said support means before saidsealing means is moved to sealing position.
 9. A well packer of thecharacter set forth in claim 6, wherein said second expander means ofsaid holddown means comprises a collet sleeve having a plurality ofresilient fingers with wedge expander means on their free ends normallyresiliently held disposed in expanding position by said fingers andcontractable by flexing of said fingers to permit release of saidgripping members from gripping position.
 10. A well packer of thecharacter set forth in claim 6, wherein said resilient means comprises:sleeve means disposed about said mandrel and spaced therefrom, andhaving means therein providing an internal annular upwardly facingshoulder intermediate the ends of the bore of said sleeve means; meanson said mandrel providing a downwardly facing stop and guide meansdisposed within the bore of said sleeve above said upwardly facingshoulder; and spring means mounted between said mandrel and said sleevemeans with the ends thereof engaging said downwardly facing guide meanson said mandrel and said upwardly facing shoulder in said sleeve means,whereby said spring means biases the lower end of said sleeve intoengagement with said gripping means to urge said gripping means togripping position when said mandrel is moved to move said packer to setposition.
 11. A well packer of the character set forth in claim 10including: operator means on said mandrel movable therewith andengageable with said support means to move said support means throughsaid sealing means toward said first gripping means after said firstgripping means has been expanded to gripping position to expand saidsealing means into sealing engagement with the wall of the well bore,said resilient means simultaneously yieldably urging said grippingmembers of said holddown means to gripping position during said movementof said mandrel and support means.
 12. A well packer of the characterset forth in claim 11, wherein said operator means is slidably carriedby said mandrel and engageable with said support means for moving saidsupport means to expand said sealing means; and yieldable connectingmeans is provided between said operator means and said mandrelreleasable to permit said mandrel to move with respect to said operatormeans to release said packer from expanded locked sealing position. 13.A well packer of the character set forth in claim 10, wherein the springbiased sleeve means of said resilient means is engageable with saidgripping members of said holddown means to urge the gripping membersthereof into expanding engagement with said second expander means and tomaintain said gripping members in expanding engagement with said secondexpander means during longitudinal movement of said mandrel setting saidpacker.
 14. A well packer of the character set forth in claim 6,including: bore wall engaging friction means connected with said firstgripping means; and means releasably connecting said mandrel with saidfriction means and said first gripping means and releasable to permitmovement of said mandrel relative thereto and with respect to saidsupport means; means on said mandrel engageable with said support meansto move said support means toward said friction means to expand saidfirst gripping means to gripping position; and means on said mandrelengageable with said support means to move said support means throughsaid sealing means toward said first gripping means to expand saidsealing means to sealing position after said first gripping means ismoved to gripping position.
 15. A well packer of the character set forthin claim 14 wherein: said lock means on said mandrel is movabletherewith out of supporting engagement with said second expander meansof said holddown means to free said second expander means for movementfrom expanding position to permit release of said gripping members ofsaid holddown means from gripping position.
 16. As a subcombination: atubular mandrel; a tubular body surrounding said mandrel and slidablelongitudinally with respect thereto; expander means on said bodycomprising a cylindrical sleeve formed with a plurality of normallyexpanded resilient fingers having external bosses on their free endsproviding cam surfaces; locking sleeve means on said mandrel movabletherewith from a position out of engagement with said expander fingersto a position to engage and support said expander fingers againstmovement toward retracted position; gripping means comprising a carrierand a plurality of slips mounted on said mandrel and movable therewithto engage said expander cam surfaces to expand said slips to grippingposition; and biasing means on said mandrel movable therewith from aposition spaces longitudinally from said gripping means to engage saidcarrier of said gripping for biasing said gripping means toward saidexpander cam surfaces to maintain said slips engaged with said camsurfaces when said mandrel is moved relative to said body means in adirection to move said locking sleeve means into position to engage andsupport said expander fingers against retraction and to move saidgripping means toward said expander means.
 17. In the subcombination ofclaim 16, coengageable latch means on said locking sleeve means and onsaid tubular body releasably engageable to secure said mandrel to saidtubular body to hold said gripping means in gripping position anddisengageable to release said mandrel from connection to said body forlongitudinal movement with respect thereto to release said grippingmeans from gripping position.
 18. In the subcombination of claim 17,means providing a longitudinal flow passage between said tubular bodyand said mandrel; and valve closure and seat means on said mandrel andsaid body engageable to close off flow through said flow passage whensaid mandrel is latched to said body.
 19. The subcombination of claim17, wherein said locking sleeve means is slidable longitudinally of saidmandrel; and means is provided yieldably securing said locking sleevemeans to said mandrel and yieldable upon application of a predeterminedlongitudinal force to said mandrel to free said mandrel from securementto said locking sleeve means for movement of said mandrel with respectto said locking sleeve means to permit said mandrel to be moved to movesaid biasing to release said gripping means without disengagement ofsaid latch means.